%  You have a choice of the following color maps:
%    hsv        - Hue-saturation-value color map.
%    hot        - Black-red-yellow-white color map.
%    gray       - Linear gray-scale color map.
%    bone       - Gray-scale with tinge of blue color map.
%    copper     - Linear copper-tone color map.
%    pink       - Pastel shades of pink color map.
%    white      - All white color map.
%    flag       - Alternating red, white, blue, and black color map.
%    lines      - Color map with the line colors.
%    colorcube  - Enhanced color-cube color map.
%    vga        - Windows colormap for 16 colors.
%    jet        - Variant of HSV.
%    prism      - Prism color map.
%    cool       - Shades of cyan and magenta color map.
%    autumn     - Shades of red and yellow color map.
%    spring     - Shades of magenta and yellow color map.
%    winter     - Shades of blue and green color map.
%    summer     - Shades of green and yellow color map.
load gallery.mat
% the above command reads array b with 30 rows and 24x16 columns
% each row corresponds to one image
p=['Size of b: ' num2str(size(b))]; % prints out the size of b
disp(p)
a=reshape(b(1,:),24,16); %this reshapes 1 row into 2D pixel array
p=['Size of a: ' num2str(size(a))];
disp(p)
colormap(gray); %this assigns colors to the image
image(a)       %this displays image
pause          %hit any key to continue
a=reshape(b(3,:),24,16);
colormap(cool(256));
image(a)
pause
a=reshape(b(3,:),24,16);
colormap(gray(256));
image(a)
pause

% the following reads and displays a bit map image
a=imread('lena128.bmp');
colormap(gray(256));
image(a)